It is found that the prior art capacitor is simply composed of an insulator coated with an alloy of tin and lead. In order to make it easier for soldering, the content of lead in the alloy is increased as much as possible (30%-90%). However, as lead is harmful to the health and environment, it is necessary to be very careful in the manufacturing process.
Therefore, it is an object of the present invention to provide a capacitor which may obviate and mitigate the above-mentioned drawbacks.